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Associating. David Levinson. Questions. How do people find jobs? Does land use pattern matter? How should JH Balance be measured? Jobs Housing Balance does it do anything? Does the market create JH balance on its own? Is JH Balance good policy?. Justifications: Congestion Air Pollution
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Associating David Levinson
Questions • How do people find jobs? • Does land use pattern matter? • How should JH Balance be measured? • Jobs Housing Balance does it do anything? • Does the market create JH balance on its own? • Is JH Balance good policy?
Justifications: Congestion Air Pollution Energy Use Quality of Life Equity/Spatial Mismatch Counter-Argument Individual Rights Transportation (Land Use) Already Subsidized Government Intervention Counter-Productive Congestion Acceptable (Min. Req. Commute) Energy Use a Market Issue There is no “Spatial Mismatch” Policy Issue: Should land use be regulated to change travel behavior?
Question: Which Scenario Produces More Traffic on the links between the cities?
Answer: • Obviously Scenario A does. In Scenario B, at least some of the workers will work in the same town in which they live. • At metropolitan or global level, jobs and houses are inevitably balanced. • It is at the sub-metropolitan geography that the issue arises.
Measuring Jobs/Housing Balance: Issues • The simplest measure is jobs housing balance in a town. However, some areas (downtown) clearly have a surplus of jobs and others a surplus of workers. Because there are economies of agglomeration at some level, it does not necessarily make sense to want the jobs to employed residents ratio equal 1 in every city or town.
Jobs Accessibility to Housing Accessibility ratio • Jobs Accessibility to Housing Accessibility ratios were analyzed for suburban Washington DC. Individuals who lived in areas with high jobs access had shorter commutes, those who lived in areas with lots of competing workers had longer commutes. The advantage of this measure is that it includes all of a region's houses and jobs, measured at a point, properly weighted by their effectiveness. • Recall that accessibility is a continuous variable which is measured by counting the number of activities (e.g. jobs) available at a given distance from an origin (e.g. the home), and discounting that number by the intervening travel time.
Wasteful Commute • What is the minimum required commute, assuming that we can move all residents to the best possible houses? • Waste = Actual commute - Minimum Required Commute.
Independence Index • Independence Index = internal work trips / total work trips
Discussion Questions: • Is self containment good? • Should Downtown Minneapolis be balanced? • Should the city of Minneapolis be balanced? • Hennepin County? • The Seven County Region? • What deviation from balance is reasonable?
Jobs Housing Balance and Transit: • Hypothesis: At a minimum, the area around the stations on a line should be balanced, preferably the area around each station.
How to correct imbalance? • Let market forces run, • Remove intervention - eliminate regulations (zoning, minimum lot size regulations, growth management) that limit ability to efficiently balance houses and jobs • Pricing - Charge more to develop in imbalanced area • Intervention - Construct additional houses in urban areas, jobs in job-poor area
Density of Some US Cities (persons per square mile) • City of Minneapolis = 6710 ppsm • City of St. Paul = 5156 • City of San Francisco 15502 • City of Boston = 11720 • City of Portland, Oregon = 3515 (note very large area) • City of Chicago = 12257 • City of Los Angeles = 7434 • City of Washington DC = 7693 (in 1998) • City of New York = 23697
Conclusions: Density or Balance? • Which matters more? • For trip generation - density • More people = more trips • For trip distribution - balance • Less balance means longer trips • For mode choice - density • Transit requires critical mass